Selection and application of fan performance (I) Description of fan performance: 1. № 10, 12, 16, 20 are converted according to dimensionless performance of № 10 model. 2. № 5, 6, 8 are converted according to dimensionless performance of № 5 model. 3. № 5 and below shall be determined according to the performance of the measured prototype. Note: According to the dimensionless performance curve conversion formula, total pressure H=ρ u2 H (Pa) flow Q=900 π D22 uQ (m3/h) shaft power N=N × D22u3 ρ/4000 (kw), where D2 - impeller outer diameter (m) u - impeller outer edge linear speed (m/s) ρ - gas density (Kg/m3), the required power rate shall be based on shaft power plus mechanical loss and motor reserve. 4. The solid line is № 5 model, and the dotted line is № 10 model. The performance of the fan is expressed by the flow, total pressure, main shaft speed, shaft power, efficiency and other parameters of the fan, and there are certain relationships between the parameters, which are listed in the following table. The relationship of fan performance parameters changes density ρ, speed n changes speed n, atmospheric pressure P, gas temperature t Q1/Q2=n1/n2 H1/H2=(n1/n2) 2 ρ 1/ρ 2 N1/N2=(n1/n2) 3 ρ 1/ρ 2 η 1=η 2 Q1/Q2=n1/n2 H1/H2=(n1/n2) 2 (P1/P2) (273+t2/273+t1) N1/N2=(n1/n2) 3 (P1/P2) (273+t2/273+t1) η 1=η 2 Note: 1. In the middle, Q represents flow (m3/h), H represents total pressure (Pa), N Represents shaft power (kw), η represents total pressure efficiency, ρ represents density (kg/m3), t represents temperature (℃), n represents speed (r/min), and P represents atmospheric pressure (Pa). 2. The footnote symbol 2 indicates the known performance and related parameters, and the footnote symbol 1 indicates the required performance and related parameters. (
colleagues Dust removal equipment manufactor What is the operation content of wet electrostatic precipitator. The dust vapor of the wet electrostatic precipitator enters the middle and lower shells through the air inlet, and the dust vapor enters the upper shell according to the precipitator. In the whole process, dust and gas are separated due to various practical functions of the dust bag. The dust removal bag expands greatly under the instantaneous reverse direction effect of the cyclone, so that the dust accumulated on the surface of the dust removal bag decreases, and the filter bag of the dust remover is modified. According to the whole cleaning process and time addition of the dedusting bag, try to stack a large amount of smoke and dust on the filter bag of the electrostatic induction precipitator. According to the size of the dedusting bag, the amount of steam gradually decreases, and the friction resistance of the dedusting bag increases. The smoke and dust are absorbed by the dust removal bag, and the vapor enters the upper shell through the filter screen pipe and is discharged from the vent. large Dust removal equipment In order to control the friction resistance within the limit range, a dedusting pulse controller is required to output steam. Open the pressure regulating valve in sequence, open the pulse solenoid valve of the wet electrostatic precipitator, and the pulse solenoid valve will instantly compress the air in the airbag. Dust falls into the silo and is discharged from the shell through the discharge valve.
The key points of factors to be considered in the technical approach to the transformation of wet electrostatic precipitators: the wet electrostatic precipitators built before the mid-1970s could not meet the requirements of the new emission standards because of the low requirements for boiler smoke and dust emissions, the small selection of equipment capacity, the outdated structure of electrostatic precipitators, aging of dust removal equipment, low dust removal efficiency and other reasons, These electrostatic precipitators have a problem of transformation to further improve efficiency. large Dust removal equipment manufactor The improvement measures for the original equipment should be considered from both technical and economic aspects, and the following technical approaches are generally adopted: 1. Discover the potential of electrostatic precipitator equipment. For example, adjust the rapping cycle and rapping force of the electrode to improve the corona power and reduce the re flying of dust; Improve the uneven distribution of flue gas velocity and readjust the technical parameters of the airflow distribution device; Adjust the control mode or power supply mode of the power supply equipment. 2、 large Dust removal equipment Combination with other dedusting equipment. That is, a primary precipitator is added before or after the electrostatic precipitator. 3. Increase the capacity (or dust collection area) of the electrostatic precipitator. That is, add an electric field, or increase or widen the electric field of the electrostatic precipitator.
Dust leakage may occur when the wet electrostatic precipitator is used at ordinary times, so that the precipitator can not achieve the expected use effect when it is used Dust removal equipment manufactor Let's specifically analyze the causes of dust leakage. 1. The dust remover is mainly assembled from the clean air chamber and the hopper. In this part, screws are used at the connection position between the upper box and the hopper. If the sealing strip used in this place is unqualified, dust will leak out. In addition to affecting the normal use of the equipment, the poor performance of the dust remover in use will have a great impact on the environment of the whole workshop and the surrounding environment. Even some wet electrostatic precipitators have a lot of materials with recycling value in the recycled dust. two colleagues large Dust removal equipment Improper filtering wind speed used in dedusting may also lead to dust leakage, because the dust will be adsorbed on the filter bag when the temperature is too high, so the resistance of dedusting equipment will increase when it is used, leading to leakage. 3. The dedusting bag is also a device that plays a major role in the operation and use of the equipment. If the density of the bag itself is relatively small, it may cause dust leakage to each other. Therefore, when selecting the bag, it is also necessary to select the one with better quality for use, and it is also necessary to do a good job of maintenance when using it again.